Slow wave sleep.
Sleep is lighter and it is easier to wake the sleeper.
Theta waves are more common.
Muscle tone, heart rate, blood pressure and body temperature all increase.
Delta waves are more common.
Duration of REM sleep increases.
Duration of NREM sleep increases.
Duration of REM sleep decreases.
The brain becomes less active.
The pattern of brain wave activity.
The presence or absence of rapid eye movements.
Sudden changes in heart rate and muscle tone.
Changes in body temperature.
Proportions of REM and NREM sleep.
External cues in the environment.
Biologically induced hormones.
Accrued sleep debt.
REM stage 1
NREM stage 2
NREM stage 3
During the night, REM sleep lengthens in duration.
During the night, REM sleep occurs after an NREM sleep cycle.
Muscle tone increases during REM sleep.
REM follows the lightest stages of sleep.
Order effects; counterbalancing
Counterbalancing; order effects
Single-blind; order effects
Order effects; confounding
Make more errors on all types of tasks
Make fewer errors on simple, boring tasks
Make more errors on complex or interesting tasks
Make more errors on simple, boring tasks
NREM stage 1
NREM stage 2
NREM stage 4
NREM stage 2 sleep.
Stage 4 sleep.
Sleep deprivation has no psychological effects.
Sleep deprivation affects one’s ability to perform cognitive tasks.
Sleep deprivation has lasting physiological effects.
The effects of sleep deprivation disappear only after the individual has slept for the same amount of time they were sleep-deprived.